The present invention relates generally to automatic accompaniment performance executed on the basis of accompaniment pattern data, and more particularly to an automatic accompaniment device which permits various variations of accompaniment performance on the basis of a same sort or group of accompaniment pattern data.
Automatic accompaniment devices are conventionally known which automatically execute an accompaniment performance in accordance with progression of a music piece on the basis of accompaniment pattern data provided for a plurality of accompaniment parts such as drum part, bass part, first chord backing part and second chord backing part. With such accompaniment devices, a particular accompaniment style is afforded by a combination of these accompaniment parts.
For the bass and chord backing parts, in the conventionally-known automatic accompaniment devices, accompaniment pattern data using a given chord (chord root and chord type) as its basic chord is converted in tone pitch (pitch-converted) through an auto. bass chord process in correspondence with a designated chord (chord root and chord type). Because the auto. bass chord process is executed in accordance with predetermined algorithms, an accompaniment performance with user desired voicing (i.e., a form of arrangement of component notes) could not necessarily be achieved on the basis of a same sort or group of accompaniment pattern data. One known approach to avoid the inconvenience has been to prepare and prestore many sorts of accompaniment pattern data in memory so that the user can select therefrom such accompaniment pattern data as to permit an accompaniment performance with desired voicing.
However, the preparation of many sorts of accompaniment pattern data was extremely time-consuming and cumbersome. In addition, in cases where many sorts of accompaniment pattern data are prestored in memory, the pattern data would occupy a great storage space in the memory, substantially reducing the size of other storage spaces that can be devoted to other data and programs. Besides, because the auto. bass chord process was executed in accordance with predetermines algorithms, an accompaniment performance could sometimes not be effected with a pitch range and sounding effect as desired by the user.